Isn't Envy thoughtful? Getting some information on how the world works, helping the team, AND still thinking about the boss back home. You can't move your operations to the reborn world if you don't have a style that your new customers appreciate.
Or the Librarian's appeal is rubbing off on the little demon and it wants to go for a prettier look! Resist the charm, Envy! A possessed scarf is more intimidating than a possessed petticoat. Wait... Is it?